<?php
// +----------------------------------------------------------------------
// | 图像操作类库
// +----------------------------------------------------------------------

class image {

	/**
     +----------------------------------------------------------
     * 裁剪缩略图  支持自动裁剪和手工裁剪
     +----------------------------------------------------------
     * @param string $src_img 原图文件名
     * @param string $dst_img 缩略图文件名
     * @param integer $dst_w 缩略图宽度
     * @param integer $dst_h 缩略图高度
     * @param integer $cut 裁剪模式 0自动等比例裁剪 1自动按原图中心裁剪 array()手工裁剪
     * @param integer $quality 缩略图质量
     +----------------------------------------------------------
     * @return void
     +----------------------------------------------------------
     */
	static function thumb($src_img,$dst_img,$dst_w=100,$dst_h=100,$cut=0,$quality=85){
		//图片详细信息
		$img = array();
		$imginfo = image::getImageInfo($src_img);
		$img['src_img'] = $src_img;
		$img['src_w'] = $src_w = $imginfo['width'];
		$img['src_h'] = $src_h = $imginfo['height'];
		$img['dst_img'] = $dst_img;
		if ($src_w<$dst_w) {
			$img['dst_w'] = $dst_w = $src_w;
		}else{
			$img['dst_w'] = $dst_w;
		}
		if ($src_h<$dst_h) {
			$img['dst_h'] = $dst_h = $src_h;
		}else{
			$img['dst_h'] = $dst_h;
		}
		$img['type'] = $type = $imginfo['type'];
		//宽高比
		$img['rate_src'] = $rate_src = $img['src_w']/$img['src_h'];
		$img['rate_dst'] = $rate_dst = $img['dst_w']/$img['dst_h'];

		if (is_numeric($cut)) { //自动裁剪
			switch($cut){
				//默认等比例缩放 大小不超过新图的长宽
				case 0:
					//目标填充大小
					if ($rate_src < $rate_dst) { //目标图高固定 求宽
						$img['fill_w'] = floor( $src_w * $dst_h / $src_h );
						$img['fill_h'] = $dst_h;
					}elseif ($rate_src > $rate_dst) { //目标图宽固定 求高
						$img['fill_w'] = $dst_w;
						$img['fill_h'] = floor( $src_h * $dst_w / $src_w );
					}else{
						$img['fill_w'] = $dst_w;
						$img['fill_h'] = $dst_h;
					}
					//原图坐标
					$img['src_x'] = 0;
					$img['src_y'] = 0;
					//原图截取大小
					$img['copy_w'] = $src_w;
					$img['copy_h'] = $src_h;
					//目标大小
					$img['dst_w'] = $img['fill_w'];
					$img['dst_h'] = $img['fill_h'];
					break;
					//按目标图大小从原图中心等比例缩放截取
				case 1:
					//原图截取大小和坐标
					if ($rate_src < $rate_dst) { //原图宽固定 求高
						$img['copy_w'] = $src_w;
						$img['copy_h'] = floor( $src_w * $dst_h / $dst_w );
						//宽固定 X坐标移动 Y坐标不变
						$img['src_x'] = 0;
						$img['src_y'] = floor( ($src_h - $img['copy_h'])/2 );
					}elseif ($rate_src > $rate_dst) { //原图高固定 求宽
						$img['copy_w'] = floor( $src_h * $dst_w / $dst_h );
						$img['copy_h'] = $src_h;
						//高固定 X坐标不变 Y坐标移动
						$img['src_x'] = floor( ($src_w - $img['copy_w'])/2 );
						$img['src_y'] = 0;
					}else{
						//原图截取大小
						$img['copy_w'] = $src_w;
						$img['copy_h'] = $src_h;
					}
					//填充大小
					$img['fill_w'] = $dst_w;
					$img['fill_h'] = $dst_h;
					break;
				default:
					//原图坐标
					$img['src_x'] = 0;
					$img['src_y'] = 0;
					//原图截取大小
					$img['copy_w'] = $src_w;
					$img['copy_h'] = $src_h;
					break;
			}
		}elseif(is_array($cut)){ //手工裁剪
			$img['src_x'] = $cut[0];
			$img['src_y'] = $cut[1];
			$img['copy_w'] = $cut[2];
			$img['copy_h'] = $cut[3];
			$img['fill_w'] = $dst_w;
			$img['fill_h'] = $dst_h;
		}else{
			return false;
		}

		//设置原图句柄
		$createFun = 'ImageCreateFrom'.($type=='jpg'?'jpeg':$type);
		if ($type == 'bmp'){
			$src_res = $this->imagecreatefrombmp($src_img);
		}else{
			$src_res = $createFun($src_img);
		}

		//检查目标图路径
		if (!is_dir(dirname($dst_img))) {
			mk_dir(dirname($dst_img));
		}

		//开始创建目标图
		$dst_res = imagecreatetruecolor($img['dst_w'], $img['dst_h']);
		$white = ImageColorAllocate($dst_res,255,255,255);
		imagefilledrectangle($dst_res,0,0,$img['fill_w'],$img['fill_h'],$white);// 填充背景色

		//复制指定大小的原图到新图
		if(function_exists("ImageCopyResampled")){
			imagecopyresampled($dst_res, $src_res, 0, 0, $img['src_x'], $img['src_y'], $img['fill_w'], $img['fill_h'], $img['copy_w'], $img['copy_h']);
		}else{
			imagecopyresized($dst_res, $src_res, 0, 0, $img['src_x'], $img['src_y'], $img['fill_w'], $img['fill_h'], $img['copy_w'], $img['copy_h']);
		}

		// 对jpeg图形设置隔行扫描
		if('jpg'==$type || 'jpeg'==$type) imageinterlace($dst_res,true);

		//输出缩略图
		$dstinfo = pathinfo($dst_img);
		$imgtype = $dstinfo['extension'];
		$imgtype = $imgtype?$imgtype:$type;
		$imageFun = 'image'.($imgtype=='jpg'?'jpeg':$imgtype);
		if($imgtype=='jpg'||$imgtype=='jpeg'){
			$imageFun($dst_res, $dst_img, $quality);
		}else{
			$imageFun($dst_res, $dst_img);
		}
		//释放资源
		imagedestroy($src_res);
		imagedestroy($dst_res);
	}

	/**
     +----------------------------------------------------------
     * 取得图像信息
     +----------------------------------------------------------
     * @param string $image 图像文件名
     +----------------------------------------------------------
     * @return mixed
     +----------------------------------------------------------
     */
	static function getImageInfo($img) {
		$imageInfo = getimagesize($img);
		if( $imageInfo!== false) {
			$imageType = strtolower(substr(image_type_to_extension($imageInfo[2]),1));
			$imageSize = filesize($img);
			$info = array(
			"width"=>$imageInfo[0],
			"height"=>$imageInfo[1],
			"type"=>$imageType,
			"size"=>$imageSize,
			"mime"=>$imageInfo['mime']
			);
			return $info;
		}else {
			return false;
		}
	}
	
	/**
      +----------------------------------------------------------
     * 为图片添加水印
      +----------------------------------------------------------
     * @param string $source 原文件名
     * @param string $water  水印图片
     * @param string $$savename  添加水印后的图片名
     * @param string $alpha  水印的透明度
      +----------------------------------------------------------
     * @return string
      +----------------------------------------------------------
     */
    static public function water($source, $water, $savename=null, $alpha=80) {
        //检查文件是否存在
        if (!file_exists($source) || !file_exists($water))
            return false;

        //图片信息
        $sInfo = self::getImageInfo($source);
        $wInfo = self::getImageInfo($water);

        //如果图片小于水印图片，不生成图片
        if ($sInfo["width"] < $wInfo["width"] || $sInfo['height'] < $wInfo['height'])
            return false;

        //建立图像
        $sCreateFun = "imagecreatefrom" . $sInfo['type'];
        $sImage = $sCreateFun($source);
        $wCreateFun = "imagecreatefrom" . $wInfo['type'];
        $wImage = $wCreateFun($water);

        //设定图像的混色模式
        imagealphablending($wImage, true);

        //图像位置,默认为右下角右对齐
        $posY = $sInfo["height"] - $wInfo["height"];
        $posX = $sInfo["width"] - $wInfo["width"];

        //生成混合图像
        imagecopymerge($sImage, $wImage, $posX, $posY, 0, 0, $wInfo['width'], $wInfo['height'], $alpha);

        //输出图像
        $ImageFun = 'Image' . $sInfo['type'];
        //如果没有给出保存文件名，默认为原图像名
        if (!$savename) {
            $savename = $source;
            @unlink($source);
        }
        //保存图像
        $ImageFun($sImage, $savename);
        imagedestroy($sImage);
    }

	function showImg($imgFile, $text='', $x='10', $y='10', $alpha='50') {
        //获取图像文件信息
        $info = image::getImageInfo($imgFile);
        if ($info !== false) {
            $createFun = str_replace('/', 'createfrom', $info['mime']);
            $im = $createFun($imgFile);
            if ($im) {
                $ImageFun = str_replace('/', '', $info['mime']);
                //水印开始
                if (!empty($text)) {
                    $tc = imagecolorallocate($im, 0, 0, 0);
                    if (is_file($text) && file_exists($text)) {//判断$text是否是图片路径
                        // 取得水印信息
                        $textInfo = image::getImageInfo($text);
                        $createFun2 = str_replace('/', 'createfrom', $textInfo['mime']);
                        $waterMark = $createFun2($text);
                        //$waterMark=imagecolorallocatealpha($text,255,255,0,50);
                        $imgW = $info["width"];
                        $imgH = $info["width"] * $textInfo["height"] / $textInfo["width"];
                        //$y	=	($info["height"]-$textInfo["height"])/2;
                        //设置水印的显示位置和透明度支持各种图片格式
                        imagecopymerge($im, $waterMark, $x, $y, 0, 0, $textInfo['width'], $textInfo['height'], $alpha);
                    } else {
                        imagestring($im, 80, $x, $y, $text, $tc);
                    }
                    //ImageDestroy($tc);
                }
                //水印结束
                if ($info['type'] == 'png' || $info['type'] == 'gif') {
                    imagealphablending($im, FALSE); //取消默认的混色模式
                    imagesavealpha($im, TRUE); //设定保存完整的 alpha 通道信息
                }
                Header("Content-type: " . $info['mime']);
                $ImageFun($im);
                @ImageDestroy($im);
                return;
            }

            //保存图像
            $ImageFun($sImage, $savename);
            imagedestroy($sImage);
            //获取或者创建图像文件失败则生成空白PNG图片
            $im = imagecreatetruecolor(80, 30);
            $bgc = imagecolorallocate($im, 255, 255, 255);
            $tc = imagecolorallocate($im, 0, 0, 0);
            imagefilledrectangle($im, 0, 0, 150, 30, $bgc);
            imagestring($im, 4, 5, 5, "no pic", $tc);
            image::output($im);
            return;
        }
    }

	/**
      +----------------------------------------------------------
     * 根据给定的字符串生成图像
      +----------------------------------------------------------
     * @param string $string  字符串
     * @param string $size  图像大小 width,height 或者 array(width,height)
     * @param string $font  字体信息 fontface,fontsize 或者 array(fontface,fontsize)
     * @param string $type 图像格式 默认PNG
     * @param integer $disturb 是否干扰 1 点干扰 2 线干扰 3 复合干扰 0 无干扰
     * @param bool $border  是否加边框 array(color)
      +----------------------------------------------------------
     * @return string
      +----------------------------------------------------------
     */
    static function buildString($string, $rgb=array(), $filename='', $type='png', $disturb=1, $border=true) {
        if (is_string($size))
            $size = explode(',', $size);
        $width = $size[0];
        $height = $size[1];
        if (is_string($font))
            $font = explode(',', $font);
        $fontface = $font[0];
        $fontsize = $font[1];
        $length = strlen($string);
        $width = ($length * 9 + 10) > $width ? $length * 9 + 10 : $width;
        $height = 22;
        if ($type != 'gif' && function_exists('imagecreatetruecolor')) {
            $im = @imagecreatetruecolor($width, $height);
        } else {
            $im = @imagecreate($width, $height);
        }
        if (empty($rgb)) {
            $color = imagecolorallocate($im, 102, 104, 104);
        } else {
            $color = imagecolorallocate($im, $rgb[0], $rgb[1], $rgb[2]);
        }
        $backColor = imagecolorallocate($im, 255, 255, 255);    //背景色（随机）
        $borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
        $pointColor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));                 //点颜色

        @imagefilledrectangle($im, 0, 0, $width - 1, $height - 1, $backColor);
        @imagerectangle($im, 0, 0, $width - 1, $height - 1, $borderColor);
        @imagestring($im, 5, 5, 3, $string, $color);
        if (!empty($disturb)) {
            // 添加干扰
            if ($disturb = 1 || $disturb = 3) {
                for ($i = 0; $i < 25; $i++) {
                    imagesetpixel($im, mt_rand(0, $width), mt_rand(0, $height), $pointColor);
                }
            } elseif ($disturb = 2 || $disturb = 3) {
                for ($i = 0; $i < 10; $i++) {
                    imagearc($im, mt_rand(-10, $width), mt_rand(-10, $height), mt_rand(30, 300), mt_rand(20, 200), 55, 44, $pointColor);
                }
            }
        }
        image::output($im, $type, $filename);
    }

	/**
     +----------------------------------------------------------
     * 生成图像验证码
     +----------------------------------------------------------
     * @param string $length  位数
     * @param string $mode  类型
     * @param string $type 图像格式
     * @param string $width  宽度
     * @param string $height  高度
     +----------------------------------------------------------
     * @return string
     +----------------------------------------------------------
     */
	static function buildImageVerify($length=4,$mode=1,$type='png',$width=48,$height=22,$verifyName='verify')
	{
		load_class('string');
		$randval = String::rand_string($length,$mode);
		$_SESSION[$verifyName]= md5($randval);
		$width = ($length*10+10)>$width?$length*10+10:$width;
		if ( $type!='gif' && function_exists('imagecreatetruecolor')) {
			$im = @imagecreatetruecolor($width,$height);
		}else {
			$im = @imagecreate($width,$height);
		}
		$r = Array(225,255,255,223);
		$g = Array(225,236,237,255);
		$b = Array(225,236,166,125);
		$key = mt_rand(0,3);

		$backColor = imagecolorallocate($im, $r[$key],$g[$key],$b[$key]);    //背景色（随机）
		$borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
		$pointColor = imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));                 //点颜色

		@imagefilledrectangle($im, 0, 0, $width - 1, $height - 1, $backColor);
		@imagerectangle($im, 0, 0, $width-1, $height-1, $borderColor);
		$stringColor = imagecolorallocate($im,mt_rand(0,200),mt_rand(0,120),mt_rand(0,120));
		// 干扰
		for($i=0;$i<10;$i++){
			$fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
			imagearc($im,mt_rand(-10,$width),mt_rand(-10,$height),mt_rand(30,300),mt_rand(20,200),55,44,$fontcolor);
		}
		for($i=0;$i<25;$i++){
			$fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
			imagesetpixel($im,mt_rand(0,$width),mt_rand(0,$height),$pointColor);
		}
		for($i=0;$i<$length;$i++) {
			imagestring($im,5,$i*10+5,mt_rand(1,8),$randval{$i}, $stringColor);
		}
		//        @imagestring($im, 5, 5, 3, $randval, $stringColor);
		image::output($im,$type);
	}

	// 中文验证码
	static function GBVerify($length=4,$type='png',$width=180,$height=50,$fontface='simhei.ttf',$verifyName='verify') {
		load_class('string');
		$code = String::rand_string($length,4);
		$width = ($length*45)>$width?$length*45:$width;
		$_SESSION[$verifyName]= md5($code);
		$im=imagecreatetruecolor($width,$height);
		$borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
		$bkcolor=imagecolorallocate($im,250,250,250);
		imagefill($im,0,0,$bkcolor);
		@imagerectangle($im, 0, 0, $width-1, $height-1, $borderColor);
		// 干扰
		for($i=0;$i<15;$i++){
			$fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
			imagearc($im,mt_rand(-10,$width),mt_rand(-10,$height),mt_rand(30,300),mt_rand(20,200),55,44,$fontcolor);
		}
		for($i=0;$i<255;$i++){
			$fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
			imagesetpixel($im,mt_rand(0,$width),mt_rand(0,$height),$fontcolor);
		}
		if(!is_file($fontface)) {
			$fontface = dirname(__FILE__)."/".$fontface;
		}
		for($i=0;$i<$length;$i++){
			$fontcolor=imagecolorallocate($im,mt_rand(0,120),mt_rand(0,120),mt_rand(0,120)); //这样保证随机出来的颜色较深。
			$codex= msubstr($code,1,$i);
			imagettftext($im,mt_rand(16,20),mt_rand(-60,60),40*$i+20,mt_rand(30,35),$fontcolor,$fontface,$codex);
		}
		image::output($im,$type);
	}

	/**
     +----------------------------------------------------------
     * 把图像转换成字符显示
     +----------------------------------------------------------
     * @param string $image  要显示的图像
     * @param string $type  图像类型，默认自动获取
     +----------------------------------------------------------
     * @return string
     +----------------------------------------------------------
     */
	static function showASCIIImg($image,$string='',$type='')
	{
		$info  = image::getImageInfo($image);
		if($info !== false) {
			$type = empty($type)?$info['type']:$type;
			unset($info);
			// 载入原图
			$createFun = 'ImageCreateFrom'.($type=='jpg'?'jpeg':$type);
			$im     = $createFun($image);
			$dx = imagesx($im);
			$dy = imagesy($im);
			$i	=	0;
			$out   =  '<span style="padding:0px;margin:0;line-height:100%;font-size:1px;">';
			set_time_limit(0);
			for($y = 0; $y < $dy; $y++) {
				for($x=0; $x < $dx; $x++) {
					$col = imagecolorat($im, $x, $y);
					$rgb = imagecolorsforindex($im,$col);
					$str	 =	 empty($string)?'*':$string[$i++];
					$out .= sprintf('<span style="margin:0px;color:#%02x%02x%02x">'.$str.'</span>',$rgb['red'],$rgb['green'],$rgb['blue']);
				}
				$out .= "<br>\n";
			}
			$out .=  '</span>';
			imagedestroy($im);
			return $out;
		}
		return false;
	}

	/**
     +----------------------------------------------------------
     * 生成高级图像验证码
     +----------------------------------------------------------
     * @param string $type 图像格式
     * @param string $width  宽度
     * @param string $height  高度
     +----------------------------------------------------------
     * @return string
     +----------------------------------------------------------
     */
	static function showAdvVerify($type='png',$width=180,$height=40,$verifyName='verifyCode')
	{
		$rand	=	range('a','z');
		shuffle($rand);
		$verifyCode	=	array_slice($rand,0,10);
		$letter = implode(" ",$verifyCode);
		$_SESSION[$verifyName] = $verifyCode;
		$im = imagecreate($width,$height);
		$r = array(225,255,255,223);
		$g = array(225,236,237,255);
		$b = array(225,236,166,125);
		$key = mt_rand(0,3);
		$backColor = imagecolorallocate($im, $r[$key],$g[$key],$b[$key]);
		$borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
		imagefilledrectangle($im, 0, 0, $width - 1, $height - 1, $backColor);
		imagerectangle($im, 0, 0, $width-1, $height-1, $borderColor);
		$numberColor = imagecolorallocate($im, 255,rand(0,100), rand(0,100));
		$stringColor = imagecolorallocate($im, rand(0,100), rand(0,100), 255);
		// 添加干扰
		/*
		for($i=0;$i<10;$i++){
		$fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
		imagearc($im,mt_rand(-10,$width),mt_rand(-10,$height),mt_rand(30,300),mt_rand(20,200),55,44,$fontcolor);
		}
		for($i=0;$i<255;$i++){
		$fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
		imagesetpixel($im,mt_rand(0,$width),mt_rand(0,$height),$fontcolor);
		}*/
		imagestring($im, 5, 5, 1, "0 1 2 3 4 5 6 7 8 9", $numberColor);
		imagestring($im, 5, 5, 20, $letter, $stringColor);
		image::output($im,$type);
	}

	/**
      +----------------------------------------------------------
     * 生成UPC-A条形码
      +----------------------------------------------------------
     * @static
      +----------------------------------------------------------
     * @param string $type 图像格式
     * @param string $type 图像格式
     * @param string $lw  单元宽度
     * @param string $hi   条码高度
      +----------------------------------------------------------
     * @return string
      +----------------------------------------------------------
     */
    static function UPCA($code, $type='png', $lw=2, $hi=100) {
        static $Lencode = array('0001101', '0011001', '0010011', '0111101', '0100011',
    '0110001', '0101111', '0111011', '0110111', '0001011');
        static $Rencode = array('1110010', '1100110', '1101100', '1000010', '1011100',
    '1001110', '1010000', '1000100', '1001000', '1110100');
        $ends = '101';
        $center = '01010';
        /* UPC-A Must be 11 digits, we compute the checksum. */
        if (strlen($code) != 11) {
            die("UPC-A Must be 11 digits.");
        }
        /* Compute the EAN-13 Checksum digit */
        $ncode = '0' . $code;
        $even = 0;
        $odd = 0;
        for ($x = 0; $x < 12; $x++) {
            if ($x % 2) {
                $odd += $ncode[$x];
            } else {
                $even += $ncode[$x];
            }
        }
        $code.= ( 10 - (($odd * 3 + $even) % 10)) % 10;
        /* Create the bar encoding using a binary string */
        $bars = $ends;
        $bars.=$Lencode[$code[0]];
        for ($x = 1; $x < 6; $x++) {
            $bars.=$Lencode[$code[$x]];
        }
        $bars.=$center;
        for ($x = 6; $x < 12; $x++) {
            $bars.=$Rencode[$code[$x]];
        }
        $bars.=$ends;
        /* Generate the Barcode Image */
        if ($type != 'gif' && function_exists('imagecreatetruecolor')) {
            $im = imagecreatetruecolor($lw * 95 + 30, $hi + 30);
        } else {
            $im = imagecreate($lw * 95 + 30, $hi + 30);
        }
        $fg = ImageColorAllocate($im, 0, 0, 0);
        $bg = ImageColorAllocate($im, 255, 255, 255);
        ImageFilledRectangle($im, 0, 0, $lw * 95 + 30, $hi + 30, $bg);
        $shift = 10;
        for ($x = 0; $x < strlen($bars); $x++) {
            if (($x < 10) || ($x >= 45 && $x < 50) || ($x >= 85)) {
                $sh = 10;
            } else {
                $sh = 0;
            }
            if ($bars[$x] == '1') {
                $color = $fg;
            } else {
                $color = $bg;
            }
            ImageFilledRectangle($im, ($x * $lw) + 15, 5, ($x + 1) * $lw + 14, $hi + 5 + $sh, $color);
        }
        /* Add the Human Readable Label */
        ImageString($im, 4, 5, $hi - 5, $code[0], $fg);
        for ($x = 0; $x < 5; $x++) {
            ImageString($im, 5, $lw * (13 + $x * 6) + 15, $hi + 5, $code[$x + 1], $fg);
            ImageString($im, 5, $lw * (53 + $x * 6) + 15, $hi + 5, $code[$x + 6], $fg);
        }
        ImageString($im, 4, $lw * 95 + 17, $hi - 5, $code[11], $fg);
        /* Output the Header and Content. */
        image::output($im, $type);
    }

	static function output($im,$type='png',$filename='')
	{
		header("Content-type: image/".$type);
		$ImageFun='image'.$type;
		if(empty($filename)) {
			$ImageFun($im);
		}else{
			$ImageFun($im,$filename);
		}
		imagedestroy($im);
	}
}

function imagebmp(&$im, $filename = '', $bit = 8, $compression = 0){
	if (!in_array($bit, array(1, 4, 8, 16, 24, 32))){
		$bit = 8;
	}else if ($bit == 32) {// todo:32 bit
		$bit = 24;
	}

	$bits = pow(2, $bit);

	// 调整调色板
	imagetruecolortopalette($im, true, $bits);
	$width  = imagesx($im);
	$height = imagesy($im);
	$colors_num = imagecolorstotal($im);

	if ($bit <= 8){
		// 颜色索引
		$rgb_quad = '';
		for ($i = 0; $i < $colors_num; $i ++){
			$colors = imagecolorsforindex($im, $i);
			$rgb_quad .= chr($colors['blue']) . chr($colors['green']) . chr($colors['red']) . "\0";
		}

		// 位图数据
		$bmp_data = '';

		// 非压缩
		if ($compression == 0 || $bit < 8){
			if (!in_array($bit, array(1, 4, 8))){
				$bit = 8;
			}

			$compression = 0;

			// 每行字节数必须为4的倍数，补齐。
			$extra = '';
			$padding = 4 - ceil($width / (8 / $bit)) % 4;
			if ($padding % 4 != 0){
				$extra = str_repeat("\0", $padding);
			}

			for ($j = $height - 1; $j >= 0; $j --){
				$i = 0;
				while ($i < $width){
					$bin = 0;
					$limit = $width - $i < 8 / $bit ? (8 / $bit - $width + $i) * $bit : 0;

					for ($k = 8 - $bit; $k >= $limit; $k -= $bit){
						$index = imagecolorat($im, $i, $j);
						$bin |= $index << $k;
						$i ++;
					}
					$bmp_data .= chr($bin);
				}
				$bmp_data .= $extra;
			}
		}
		// RLE8 压缩
		else if ($compression == 1 && $bit == 8){
			for ($j = $height - 1; $j >= 0; $j --){
				$last_index = "\0";
				$same_num   = 0;
				for ($i = 0; $i <= $width; $i ++){
					$index = imagecolorat($im, $i, $j);
					if ($index !== $last_index || $same_num > 255){
						if ($same_num != 0){
							$bmp_data .= chr($same_num) . chr($last_index);
						}
						$last_index = $index;
						$same_num = 1;
					}else{
						$same_num ++;
					}
				}
				$bmp_data .= "\0\0";
			}
			$bmp_data .= "\0\1";
		}
		$size_quad = strlen($rgb_quad);
		$size_data = strlen($bmp_data);
	}else{
		// 每行字节数必须为4的倍数，补齐。
		$extra = '';
		$padding = 4 - ($width * ($bit / 8)) % 4;
		if ($padding % 4 != 0){
			$extra = str_repeat("\0", $padding);
		}

		// 位图数据
		$bmp_data = '';

		for ($j = $height - 1; $j >= 0; $j --){
			for ($i = 0; $i < $width; $i ++){
				$index  = imagecolorat($im, $i, $j);
				$colors = imagecolorsforindex($im, $index);

				if ($bit == 16){
					$bin = 0 << $bit;

					$bin |= ($colors['red'] >> 3) << 10;
					$bin |= ($colors['green'] >> 3) << 5;
					$bin |= $colors['blue'] >> 3;

					$bmp_data .= pack("v", $bin);
				}else{
					$bmp_data .= pack("c*", $colors['blue'], $colors['green'], $colors['red']);
				}
				// todo: 32bit;
			}
			$bmp_data .= $extra;
		}
		$size_quad = 0;
		$size_data = strlen($bmp_data);
		$colors_num = 0;
	}

	// 位图文件头
	$file_header = "BM" . pack("V3", 54 + $size_quad + $size_data, 0, 54 + $size_quad);

	// 位图信息头
	$info_header = pack("V3v2V*", 0x28, $width, $height, 1, $bit, $compression, $size_data, 0, 0, $colors_num, 0);

	// 写入文件
	if ($filename != ''){
		$fp = fopen($filename, "wb");
		fwrite($fp, $file_header);
		fwrite($fp, $info_header);
		fwrite($fp, $rgb_quad);
		fwrite($fp, $bmp_data);
		fclose($fp);
		return 1;
	}

	// 浏览器输出
	header("Content-Type: image/bmp");
	echo $file_header . $info_header;
	echo $rgb_quad;
	echo $bmp_data;

	return 1;
}
function imagecreatefrombmp($file){
	global  $CurrentBit, $echoMode;
	$f=fopen($file,"r");
	$Header=fread($f,2);

	if($Header=="BM"){
		$Size=freaddword($f);
		$Reserved1=freadword($f);
		$Reserved2=freadword($f);
		$FirstByteOfImage=freaddword($f);

		$SizeBITMAPINFOHEADER=freaddword($f);
		$Width=freaddword($f);
		$Height=freaddword($f);
		$biPlanes=freadword($f);
		$biBitCount=freadword($f);
		$RLECompression=freaddword($f);
		$WidthxHeight=freaddword($f);
		$biXPelsPerMeter=freaddword($f);
		$biYPelsPerMeter=freaddword($f);
		$NumberOfPalettesUsed=freaddword($f);
		$NumberOfImportantColors=freaddword($f);

		if($biBitCount<24){
			$img=imagecreate($Width,$Height);
			$Colors=pow(2,$biBitCount);
			for($p=0;$p<$Colors;$p++){
				$B=freadbyte($f);
				$G=freadbyte($f);
				$R=freadbyte($f);
				$Reserved=freadbyte($f);
				$Palette[]=imagecolorallocate($img,$R,$G,$B);
			}
			if($RLECompression==0){
				$Zbytek=(4-ceil(($Width/(8/$biBitCount)))%4)%4;
				for($y=$Height-1;$y>=0;$y--){
					$CurrentBit=0;
					for($x=0;$x<$Width;$x++){
						$C=freadbits($f,$biBitCount);
						imagesetpixel($img,$x,$y,$Palette[$C]);
					}
					if($CurrentBit!=0) {freadbyte($f);}
					for($g=0;$g<$Zbytek;$g++)
					freadbyte($f);
				}
			}
		}

		if($RLECompression==1) //$BI_RLE8
		{
			$y=$Height;
			$pocetb=0;
			while(true){
				$y--;
				$prefix=freadbyte($f);
				$suffix=freadbyte($f);
				$pocetb+=2;

				$echoit=false;

				if($echoit)echo "Prefix: $prefix Suffix: $suffix<BR>";
				if(($prefix==0)and($suffix==1)) break;
				if(feof($f)) break;

				while(!(($prefix==0)and($suffix==0))){
					if($prefix==0){
						$pocet=$suffix;
						$Data.=fread($f,$pocet);
						$pocetb+=$pocet;
						if($pocetb%2==1) {freadbyte($f); $pocetb++;}
					}
					if($prefix>0){
						$pocet=$prefix;
						for($r=0;$r<$pocet;$r++)
						$Data.=chr($suffix);
					}
					$prefix=freadbyte($f);
					$suffix=freadbyte($f);
					$pocetb+=2;
					if($echoit) echo "Prefix: $prefix Suffix: $suffix<BR>";
				}

				for($x=0;$x<strlen($Data);$x++){
					imagesetpixel($img,$x,$y,$Palette[ord($Data[$x])]);
				}
				$Data="";
			}
		}

		if($RLECompression==2) //$BI_RLE4
		{
			$y=$Height;
			$pocetb=0;

			while(true){
				//break;
				$y--;
				$prefix=freadbyte($f);
				$suffix=freadbyte($f);
				$pocetb+=2;

				$echoit=false;

				if($echoit)echo "Prefix: $prefix Suffix: $suffix<BR>";
				if(($prefix==0)and($suffix==1)) break;
				if(feof($f)) break;

				while(!(($prefix==0)and($suffix==0))){
					if($prefix==0){
						$pocet=$suffix;

						$CurrentBit=0;
						for($h=0;$h<$pocet;$h++)
						$Data.=chr(freadbits($f,4));
						if($CurrentBit!=0) freadbits($f,4);
						$pocetb+=ceil(($pocet/2));
						if($pocetb%2==1) {freadbyte($f); $pocetb++;}
					}
					if($prefix>0){
						$pocet=$prefix;
						$i=0;
						for($r=0;$r<$pocet;$r++){
							if($i%2==0){
								$Data.=chr($suffix%16);
							}else{
								$Data.=chr(floor($suffix/16));
							}
							$i++;
						}
					}
					$prefix=freadbyte($f);
					$suffix=freadbyte($f);
					$pocetb+=2;
					if($echoit) echo "Prefix: $prefix Suffix: $suffix<BR>";
				}
				for($x=0;$x<strlen($Data);$x++){
					imagesetpixel($img,$x,$y,$Palette[ord($Data[$x])]);
				}
				$Data="";
			}
		}
		if($biBitCount==24){
			$img=imagecreatetruecolor($Width,$Height);
			$Zbytek=$Width%4;

			for($y=$Height-1;$y>=0;$y--){
				for($x=0;$x<$Width;$x++){
					$B=freadbyte($f);
					$G=freadbyte($f);
					$R=freadbyte($f);
					$color=imagecolorexact($img,$R,$G,$B);
					if($color==-1) $color=imagecolorallocate($img,$R,$G,$B);
					imagesetpixel($img,$x,$y,$color);
				}
				for($z=0;$z<$Zbytek;$z++)
				freadbyte($f);
			}
		}
		return $img;
	}
	fclose($f);
}

function freadbyte($f){
	return ord(fread($f,1));
}
function freadword($f){
	$b1=freadbyte($f);
	$b2=freadbyte($f);
	return $b2*256+$b1;
}
function freaddword($f){
	$b1=freadword($f);
	$b2=freadword($f);
	return $b2*65536+$b1;
}
?>